U.S. patent application number 14/017536 was filed with the patent office on 2014-03-13 for torque fluctuation reducing apparatus.
This patent application is currently assigned to AISIN SEIKI KABUSHIKI KAISHA. The applicant listed for this patent is AISIN SEIKI KABUSHIKI KAISHA. Invention is credited to Masaru EBATA, Takashi HORI, Hiroshi KAWAZOE, Yusaku NISHIO, Tomohiro SAEKI, Yoshihiro TAKIKAWA.
Application Number | 20140069228 14/017536 |
Document ID | / |
Family ID | 49000384 |
Filed Date | 2014-03-13 |
United States Patent
Application |
20140069228 |
Kind Code |
A1 |
SAEKI; Tomohiro ; et
al. |
March 13, 2014 |
TORQUE FLUCTUATION REDUCING APPARATUS
Abstract
A torque fluctuation reducing apparatus includes a first main
damper provided on a power transmission path between a drive source
and a transmission, and reducing fluctuation torque generated
between the drive source and the transmission, a second main damper
provided at a transmission-side relative to the first main damper
to be in series with the first main damper and reducing the
fluctuation torque, the second main damper including a vibration
damping property which is different from a vibration damping
property of the first main damper, a dynamic damper provided
between the first main damper and the second main damper, and
restricting vibration at a specific resonance point of a drive
system on the power transmission path by using an inertia body and
an elastic force, a chamber accommodating the first and the second
main dampers, and the dynamic damper, and a viscous medium enclosed
in part of the chamber.
Inventors: |
SAEKI; Tomohiro; (Anjo-shi,
JP) ; KAWAZOE; Hiroshi; (Kariya-shi, JP) ;
NISHIO; Yusaku; (Chiryu-shi, JP) ; EBATA; Masaru;
(Chita-shi, JP) ; HORI; Takashi; (Anjo-shi,
JP) ; TAKIKAWA; Yoshihiro; (Tsushima-shi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AISIN SEIKI KABUSHIKI KAISHA |
Aichi-ken |
|
JP |
|
|
Assignee: |
AISIN SEIKI KABUSHIKI
KAISHA
Aichi-ken
JP
|
Family ID: |
49000384 |
Appl. No.: |
14/017536 |
Filed: |
September 4, 2013 |
Current U.S.
Class: |
74/573.12 |
Current CPC
Class: |
F16F 15/12366 20130101;
Y10T 74/2125 20150115; F16F 15/163 20130101; F16F 15/13484
20130101; F16F 15/1428 20130101; F16F 15/1421 20130101 |
Class at
Publication: |
74/573.12 |
International
Class: |
F16F 15/14 20060101
F16F015/14 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 7, 2012 |
JP |
2012-196816 |
Claims
1. A torque fluctuation reducing apparatus, comprising: a first
main damper provided on a power transmission path between a drive
source and a transmission, and reducing, by using an elastic force,
fluctuation torque generated between the drive source and the
transmission; a second main damper provided at a transmission-side
relative to the first main damper to be in series with the first
main damper on the power transmission path, and reducing, by using
an elastic force, the fluctuation torque generated between the
drive source and the transmission, the second main damper including
a vibration damping property which is different from a vibration
damping property of the first main damper; a dynamic damper
provided on the power transmission path between the first main
damper and the second main damper, and restricting vibration at a
specific resonance point of a drive system on the power
transmission path by using an inertia body and an elastic force; a
chamber accommodating the first main damper and the second main
damper, and the dynamic damper; and a viscous medium enclosed in
part of the chamber.
2. The torque fluctuation reducing apparatus according to claim 1,
wherein the first main damper is arranged radially outwardly
relative to the second main damper.
3. The torque fluctuation reducing apparatus according to claim 2,
wherein the first main damper is set to be immersed in the viscous
medium accumulating at a radially outward portion in the chamber
when the torque fluctuation reducing apparatus rotates.
4. The torque fluctuation reducing apparatus according to claim 2,
wherein the first main damper includes an arc coil spring which is
formed in a circular arc-shape and which reduces the fluctuation
torque generated between the drive source and the transmission.
5. The torque fluctuation reducing apparatus according to claim 1,
further comprising: a cover plate covering the chamber, the cover
plate serving as part of a first power transmission member on the
power transmission path at a drive source-side relative to the
first main damper, and serving as part of a component member of the
first main damper.
6. The torque fluctuation reducing apparatus according to claim 5,
further comprising: a seal member sealing a clearance between a
second power transmission member on the power transmission path at
the transmission-side relative to the second main damper and the
cover plate, wherein the cover plate is formed in an annular shape
and is extended radially inwardly relative to the first main damper
and the second main damper, and the dynamic damper.
7. The torque fluctuation reducing apparatus according to claim 1,
wherein the second main damper includes a first coil spring for
reducing the fluctuation torque generated between the drive source
and the transmission, and a first seat member made of resin and
arranged at each end of the first coil spring, and the dynamic
damper includes a second coil spring for restricting vibration at a
specific resonance point of a rotative power from the drive source,
and a second seat member made of resin and arranged at each end of
the second coil spring.
8. The torque fluctuation reducing apparatus according to claim 1,
wherein the dynamic damper is provided at plural positions on the
power transmission path between the first main damper and the
second main damper in a manner that the plural dynamic dampers are
parallel to each other on the power transmission path.
9. The torque fluctuation reducing apparatus according to claim 8,
wherein each of the plural dynamic dampers includes a different
resonance frequency from each other.
10. The torque fluctuation reducing apparatus according to claim 9,
wherein one or both of the elastic force and the inertia body of
each of the plural dynamic dampers is different from each
other.
11. The torque fluctuation reducing apparatus according to claim 8,
wherein one or more of the plural dynamic dampers is arranged at
one side and the rest of the dynamic dampers is arranged at the
other side in an axial direction of the torque fluctuation reducing
apparatus relative to the first main damper and the second main
damper.
12. The torque fluctuation reducing apparatus according to claim 8,
wherein part of the inertia body of at least one of the plural
dynamic dampers is set to be immersed in the viscous medium
accumulating at a radially outward portion in the chamber when the
torque fluctuation reducing apparatus rotates.
13. The torque fluctuation reducing apparatus according to claim
12, wherein the inertia body, the part of which is immersed in the
viscous medium when the torque fluctuation reducing apparatus
rotates, includes a recessed-and-protruding portion, a through hole
or a corrugated portion which increases resistance when the inertia
body moves in the viscous medium.
14. The torque fluctuation reducing apparatus according to claim
12, wherein the inertia body, the part of which is immersed in the
viscous medium when the torque fluctuation reducing apparatus
rotates, is provided with a block which increases resistance when
the inertia body moves in the viscous medium.
15. The torque fluctuation reducing apparatus according to claim
12, wherein the inertia body, the part of which is immersed in the
viscous medium when the torque fluctuation reducing apparatus
rotates, includes a recessed portion which reduces resistance when
the inertia body moves in the viscous medium.
16. The torque fluctuation reducing apparatus according to claim 1,
wherein the viscous medium corresponds to oil or grease of which
viscosity resistance increases as the oil or the grease cools.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
U.S.C. .sctn.119 to Japanese Patent Application 2012-196816, filed
on Sep. 7, 2012, the entire content of which is incorporated herein
by reference.
TECHNICAL FIELD
[0002] This disclosure generally relates to a torque fluctuation
reducing apparatus.
BACKGROUND DISCUSSION
[0003] A torque fluctuation reducing apparatus is provided on a
power transmission path between an engine serving as a drive source
and a transmission, and reduces (absorbs, restricts) fluctuation
torque generated between the engine and the transmission. The
torque fluctuation reducing apparatus may include a damper
mechanism which absorbs the fluctuation torque by means of an
elastic force (a spring force). The damper mechanism includes a
configuration where an elastic member (a coil spring) is arranged
between two rotating members in a circumferential direction thereof
so that the coil spring is compressed when the two rotating members
rotate relative to each other, and thus the fluctuation torque is
reduced.
[0004] A known torque fluctuation reducing apparatus may be
provided with two kinds of damper mechanisms (a coil spring, an
elastic member) which are arranged in series with each other so
that the fluctuation torque is restricted in response to a driving
status of an engine (for example, at start-up, at idling, and so
forth) (for example, refer to JP2010-38312A which is hereinafter
referred to as Patent reference 1).
[0005] In addition, in order to achieve an enhanced vibration
damping performance during driving at low speeds, the known torque
fluctuation reducing apparatus may be provided with a dynamic
damper where an inertia body (an inertia member) is elastically
connected via an elastic body (an elastic member) to the damper
mechanism which is provided at a lock-up apparatus at a torque
converter between the engine and the transmission (for example,
refer to JP2009-293671A and JP2012-77811A which are hereinafter
referred to as Patent references 2 and 3, respectively).
[0006] According to the known torque fluctuation reducing apparatus
of Patent reference 1, simply arranging the two kinds of damper
mechanisms in series with each other provides a limited absorption
of the fluctuation torque. Accordingly, there is a need for further
reducing vibrations of a vehicle and noises of the vehicle.
[0007] According to the known torque fluctuation reducing
apparatuses of Patent references 2 and 3, a seat is not applied to
an end portion of the elastic body (the elastic member) of the
dynamic damper, which causes no problem in a case where the dynamic
damper is used in oil circulating inside the torque converter.
However, in a case where the known torque fluctuation reducing
apparatus is applied to a case where the dynamic damper is used in
a viscous medium which does not circulate, wear may progress at the
elastic body (the elastic member) or at the rotating members. In
addition, according to the known torque fluctuation reducing
apparatuses of Patent references 2 and 3, the inertia body of the
dynamic damper is in a state where the inertia body is always hard
to move because the inertia body of the dynamic damper is in a
chamber which is filled with oil in the torque converter.
Accordingly, an aimed vibration damping performance may not be
obtained.
[0008] A need thus exists for a torque fluctuation reducing
apparatus which is not susceptible to the drawback mentioned
above.
SUMMARY
[0009] According to an aspect of this disclosure, a torque
fluctuation reducing apparatus includes a first main damper
provided on a power transmission path between a drive source and a
transmission, and reducing, by using an elastic force, fluctuation
torque generated between the drive source and the transmission, a
second main damper provided at a transmission-side relative to the
first main damper to be in series with the first main damper on the
power transmission path, and reducing, by using an elastic force,
the fluctuation torque generated between the drive source and the
transmission, the second main damper including a vibration damping
property which is different from a vibration damping property of
the first main damper, a dynamic damper provided on the power
transmission path between the first main damper and the second main
damper, and restricting vibration at a specific resonance point of
a drive system on the power transmission path by using an inertia
body and an elastic force, a chamber accommodating the first main
damper and the second main damper and the dynamic damper, and a
viscous medium enclosed in part of the chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing and additional features and characteristics of
this disclosure will become more apparent from the following
detailed description considered with the reference to the
accompanying drawings, wherein:
[0011] FIG. 1 is a cross-sectional view schematically illustrating
a configuration of a torque fluctuation reducing apparatus
according to a first embodiment disclosed here, which is taken
along line I-I in FIG. 2;
[0012] FIG. 2 is a partially cutaway plan view schematically
illustrating the configuration of the torque fluctuation reducing
apparatus according to the first embodiment;
[0013] FIG. 3A is a cross-sectional view taken along IIIA-IIIA in
FIG. 3B, which schematically illustrates a configuration of a
center plate and an inertia body of a first dynamic damper of the
torque fluctuation reducing apparatus according to the first
embodiment;
[0014] FIG. 3B is a partial plan view schematically illustrating
the configuration of the center plate and the inertia body of the
first dynamic damper of the torque fluctuation reducing apparatus
according to the first embodiment;
[0015] FIG. 4 is a schematic view illustrating an example of a
power transmission path including the torque fluctuation reducing
apparatus according to the first embodiment;
[0016] FIG. 5 is a diagram for explaining an operation of the
torque fluctuation reducing apparatus according to the first
embodiment;
[0017] FIG. 6A is a cross-sectional view taken along VIA-VIA in
FIG. 6B, which schematically illustrates a configuration of a
center plate of a first dynamic damper of a torque fluctuation
reducing apparatus according to a second embodiment disclosed
here;
[0018] FIG. 6B is a partial plan view schematically illustrating
the configuration of the center plate of the first dynamic damper
of the torque fluctuation reducing apparatus according to the
second embodiment;
[0019] FIG. 7A is a cross-sectional view taken along VIIA-VIIA in
FIG. 7B, which schematically illustrates a configuration of a
center plate of a first dynamic damper of a torque fluctuation
reducing apparatus according to a third embodiment disclosed
here;
[0020] FIG. 7B is a partial plan view schematically illustrating
the configuration of the center plate of the first dynamic damper
of the torque fluctuation reducing apparatus according to the third
embodiment;
[0021] FIG. 8A is a cross-sectional view taken along VIIIA-VIIIA in
FIG. 8B, which schematically illustrates a configuration of a
center plate of a first dynamic damper of a torque fluctuation
reducing apparatus according to a fourth embodiment disclosed
here;
[0022] FIG. 8B is a partial plan view schematically illustrating
the configuration of the center plate of the first dynamic damper
of the torque fluctuation reducing apparatus according to the
fourth embodiment;
[0023] FIG. 9A is a cross-sectional view taken along IXA-IXA in
FIG. 9B, which schematically illustrates a configuration of a
center plate and an inertia body block of a first dynamic damper of
a torque fluctuation reducing apparatus according to a fifth
embodiment disclosed here;
[0024] FIG. 9B is a partial plan view schematically illustrating
the configuration of the center plate and the inertia body block of
the first dynamic damper of the torque fluctuation reducing
apparatus according to the fifth embodiment;
[0025] FIG. 9C is a plan view schematically illustrating the
configuration of the center plate and the inertia body block of the
first dynamic damper of the torque fluctuation reducing apparatus
according to the fifth embodiment, which is seen from a direction
of an arrow Z in FIG. 9B;
[0026] FIG. 10A is a cross-sectional view taken along XA-XA in FIG.
10B, which schematically illustrates a configuration of a center
plate of a first dynamic damper of a torque fluctuation reducing
apparatus according to a sixth embodiment disclosed here;
[0027] FIG. 10B is a partial plan view schematically illustrating
the configuration of the center plate of the first dynamic damper
of the torque fluctuation reducing apparatus according to the sixth
embodiment;
[0028] FIG. 100 is a plan view schematically illustrating the
configuration of the center plate of the first dynamic damper of
the torque fluctuation reducing apparatus according to the sixth
embodiment, which is seen from a direction of an arrow Z in FIG.
10B;
[0029] FIG. 10D is a plan view schematically illustrating a
configuration of a center plate of a first dynamic damper of a
torque fluctuation reducing apparatus according to a modification
of the sixth embodiment, which is seen from a direction which
corresponds to the direction of the arrow Z in FIG. 10B;
[0030] FIG. 11A is a cross-sectional view taken along XIA-XIA in
FIG. 11B, which schematically illustrates a configuration of a
center plate of a first dynamic damper of a torque fluctuation
reducing apparatus according to a seventh embodiment disclosed
here; and
[0031] FIG. 11B is a partial plan view schematically illustrating
the configuration of the center plate of the first dynamic damper
of the torque fluctuation reducing apparatus according to the
seventh embodiment.
DETAILED DESCRIPTION
Overview of Embodiments
[0032] A torque fluctuation reducing apparatus according to
embodiments disclosed here, includes a first main damper (the first
main damper 3a in FIG. 1) provided on a power transmission path
between a drive source (an engine or ENG 1 in FIG. 4) and a
transmission (the transmission or TM 7 in FIG. 4), and reducing, by
using an elastic force, fluctuation torque generated between the
drive source and the transmission, a second main damper (the second
main damper 3b in FIG. 1) provided at a transmission-side relative
to the first main damper to be in series with the first main damper
on the power transmission path, and reducing, by using an elastic
force, the fluctuation torque generated between the drive source
and the transmission, the second main damper including a vibration
damping property which is different from a vibration damping
property of the first main damper, a dynamic damper (first and
second dynamic dampers 3c, 3d in FIG. 1) provided on the power
transmission path between the first main damper and the second main
damper, and restricting vibration at a specific resonance point of
a drive system on the power transmission path by using an inertia
body (an inertia body portion 34d, an inertia body 35, an inertia
body portion 45c in FIG. 1) and an elastic force, a chamber (the
chamber 53 in FIG. 1) accommodating the first main damper and the
second main damper, and the dynamic damper, and a viscous medium
(the viscous medium 54 in FIG. 1) enclosed in part of the
chamber.
[0033] In embodiments disclosed here, reference numerals are for
enhancing understanding and are not provided to intend to limit the
embodiments to those illustrated in the drawings. The embodiments
related to this disclosure will be explained hereunder with
reference to the drawings.
[0034] A torque fluctuation reducing apparatus according to a first
embodiment will be explained with reference to the drawings (refer
to FIGS. 1 to 4).
[0035] A torque fluctuation reducing apparatus 3 is provided on a
power transmission path between an engine 1 and a transmission 7
(between the engine 1 and a motor generator 5 in a case where the
motor generator 5 is provided as illustrated in FIG. 4), and
reduces (absorbs, restricts) fluctuation torque generated between
the engine 1 and the transmission 7 (refer to FIG. 4). A rotative
power of the engine 1 is inputted via a crankshaft 2 to the torque
fluctuation reducing apparatus 3, and the torque fluctuation
reducing apparatus 3 outputs the inputted rotative power via a
rotational shaft 4, the motor generator 5 and a rotational shaft 6
toward the transmission 7.
[0036] Here, the engine 1 serves as a drive source (an internal
combustion engine) which explodes and combusts fuel in a cylinder,
and causes the rotative power to be outputted from the crankshaft 2
by thermal energy associated to the explosion and the combustion.
The engine 1 is connected via the crankshaft 2 to the torque
fluctuation reducing apparatus 3 (refer to FIG. 4). In addition,
the motor generator 5 is a generator motor which drives as an
electric motor and drives also as an electric generator. The motor
generator 5 is connected via the rotational shaft 4 to the torque
fluctuation reducing apparatus 3, and is connected via the
rotational shaft 6 to the transmission 7 (refer to FIG. 4). In
addition, the transmission 7 (refer to FIG. 4) is a mechanism which
changes speed of the rotative power from the rotational shaft 6 and
outputs the rotative power, whose speed has been changed, toward a
differential arrangement.
[0037] The torque fluctuation reducing apparatus 3 includes plural
main dampers (a first main damper 3a and a second main damper 3b)
which are arranged in series with each other on the power
transmission path between the crankshaft 2 and the rotational shaft
4. The torque fluctuation reducing apparatus 3 includes a dynamic
damper, for example, plural dynamic dampers (a first dynamic damper
3c and a second dynamic damper 3d) which are arranged in parallel
with each other on the power transmission path (at intermediate
plates 18, 21) between the first main damper 3a and the second main
damper 3b (refer to FIGS. 1, 2 and 4).
[0038] The first main damper 3a and the second main damper 3b are
mechanisms which transmit the power from the engine 1 to the
transmission 7, and reduce (absorb, restrict) the fluctuation
torque generated between the engine 1 and the transmission 7 by
using an elastic force. The first main damper 3a is set in such a
manner that a vibration damping property of the first main damper
3a is different from a vibration damping property of the second
main damper 3b (respective spring constants of the first main
damper 3a and the second main damper 3b are set to be different
from each other). The first main damper 3a is arranged radially
outwardly (that is, outwardly in a radial direction where a central
axis 8 is a center of rotation of the crankshaft 2 and other
members) relative to the second main damper 3b. Thus, a space of
the apparatus in an axial direction may be reduced.
[0039] The first dynamic damper 3c and the second dynamic damper 3d
are mechanisms which restrict vibrations, by using the elastic
force, at a specific resonance point of a drive system on the power
transmission path. The first dynamic damper 3c is set in such a
manner that a characteristic property of the first dynamic damper
3c is different from a characteristic property of the second
dynamic damper 3d. The first dynamic damper 3c is the mechanism
where an inertia body (an inertia body portion 34d, an inertia body
35) is elastically, that is, via a coil spring 36, connected to
side plates 30, 32. The second dynamic damper 3d is the mechanism
where the inertia body (an inertia body portion 45c) is
elastically, that is, via a coil spring 46, connected to side
plates 41, 43. The first dynamic damper 3c is set in such a manner
that a resonance frequency of the first dynamic damper 3c is
different from a resonance frequency of the second dynamic damper
3d (one or both of the spring constant and a value of the inertia
is set to be different between the first dynamic damper 3c and the
second dynamic damper 3d). Thus, the vibrations may be restricted
at resonance points of plural systems. The first dynamic damper 3c
is arranged at an engine-side (at the right side in FIG. 1)
relative to the main dampers 3a, 3b, and the second dynamic damper
3d is arranged at a transmission-side (at the left side in FIG. 1)
relative to the main dampers 3a, 3b. That is, one of the dynamic
dampers 3c, 3d is arranged at one side and the rest of the dynamic
dampers 3c, 3d is arranged at the other side in the axial direction
of the torque fluctuation reducing apparatus 3 relative to the
first main damper 3a and the second main damper 3b. Accordingly,
forces applied to the main dampers 3a, 3b are well-balanced, which
is favorable to strength of the apparatus.
[0040] According to the torque fluctuation reducing apparatus 3,
the main dampers 3a, 3b and the dynamic dampers 3c, 3d are
accommodated in a chamber (the chamber 53 in FIG. 1) which is
surrounded by a cover plate 16, a disc spring 51, a thrust member
50, a hub member 23, a thrust member 38, a cover plate 14 and a
plate 15), and a viscous medium 54 is enclosed in the chamber 53
partly, that is, the viscous medium 54 is enclosed in part of the
chamber 53. The viscous medium 54 is enclosed in the chamber 53 so
that at least part of the first main damper 3a and part of the
inertia body (the inertia body portion 34d, the inertia body 35) of
the first dynamic damper 3c are immersed in, that is, are in
contact with the viscous medium 54 in a case where the torque
fluctuation reducing apparatus 3 rotates (that is, in a state where
the viscous medium 54 accumulates or stays at a radially outward
portion in the chamber 53 due to a centrifugal force). Accordingly,
component members of the first main damper 3a are restricted from
wearing. In addition, by optimizing or adjusting a resistance of
inertia of the first dynamic damper 3c, abnormal noises are
restricted in a case where a transitional vibration occurs at, for
example, an engine start-up. These abnormal noises are generated
when movement of the inertia, that is, the inertia body portion 34d
and the inertia body 35, of the first dynamic damper 3c is
restrained. As the viscous medium 54, for example, oil or grease
whose viscosity resistance increases as the oil or the grease cools
may be used. In a state where the engine 1 is cold, a rotational
resistance of the engine 1 increases and a start-up performance of
the engine 1 deteriorates, and therefore the damper is likely to
resonate. However, by using the oil or grease whose viscosity
resistance increases when the engine is cold, the resonance is
restricted and the start-up performance of the engine 1 may be
enhanced. In addition, the occurrence of the abnormal noises for
suppressing the movement of the inertia of the first dynamic damper
3c is restricted.
[0041] The torque fluctuation reducing apparatus 3 includes, as
main components thereof, a drive plate 10, a bolt 11 (for example,
plural bolts 11), a set bolt 12 (for example, plural set bolts 12),
a nut 13 (for example, plural nuts 13), the cover plate 14, the
plate 15, the cover plate 16, an inertia body 17, the intermediate
plate 18, a coil spring 19, a guide member 20, the intermediate
plate 21, a rivet 22 (for example, plural rivets 22), the hub
member 23, coil springs 24, 25, a seat member 26, thrust members
27, 28, a disc spring 29, the side plate 30, a rivet 31 (for
example, plural rivets 31), the side plate 32, a rivet 33, a center
plate 34, the inertia body 35, the coil spring 36, a seat member
37, thrust members 38, 39, 40, the side plate 41, a rivet 42 (for
example, plural rivets 42), the side plate 43, a rivet 44, a center
plate 45, the coil spring 46, a seat member 47, thrust members 48,
49, 50 and the disc spring 51.
[0042] The drive plate 10 is an annular-shaped and disc-shaped
plate for transmitting (inputting) the rotative power from the
crankshaft 2 to the torque fluctuation reducing apparatus 3 (refer
to FIG. 1). The drive plate 10 is fastened (connected) to the
crankshaft 2 at a radially inward portion of the drive plate 10 by
means of the plural bolts 11. Thus, the drive plate 10 rotates
integrally with the crankshaft 2. The drive plate 10 is fastened by
means of the plural nuts 13 to the corresponding set bolts 12 at a
radially outward portion of the drive plate 10.
[0043] Each of the set bolts 12 is a block-shaped member for
fastening the drive plate 10 by means of the corresponding nut 13
(refer to FIGS. 1 and 2). The set bolt 12 is fixed by welding at
the cover plate 14 at a surface of the cover plate 14 which is at a
side of the crankshaft 2, that is, the surface which faces a
direction of the crankshaft 2, at plural positions. The set bolt 12
includes a male thread portion screwed into the nut 13. The set
bolt 12 is fastened (connected) to the drive plate 10 by means of
the nut 13, and therefore the set bolt 12 rotates integrally with
the drive plate 10 and with the cover plate 14.
[0044] The cover plate 14 serves as a first power transmission
member which is formed in an annular shape and which covers an
engine-side (the right side in FIG. 1) of the chamber 53 (refer to
FIGS. 1 and 2). The cover plate 14 is closely attached to the cover
plate 16 via the plate 15, at a radially outward portion of the
cover plate 14 across an entire circumference thereof, and is fixed
by welding to the plate 15 and to the cover plate 16. Thus, the
cover plate 14 rotates integrally with the plate 15 and with the
cover plate 16, and the viscous medium 54 inside the chamber 53
does not leak out from a connection portion at which the cover
plate 14, the plate 15 and the cover plate 16 are joined to one
another. The inertia body 17 formed in an annular shape is fixed by
welding to the cover plate 14, at the radially outward portion of
the cover plate 14. Thus, the cover plate 14 rotates integrally
with the inertia body 17. The plural set bolts 12 are fixed by
welding to the cover plate 14 at the surface of the cover plate 14
which is at the side of the drive plate 10, that is, the surface
which faces the direction of the drive plate 10. The cover plate 14
extends radially inwardly relative to the coil springs 19, 24, 25,
36, 46 of the main dampers 3a, 3b and the dynamic dampers 3c, 3d,
respectively. The cover plate 14 is slidably in pressure contact
with the thrust member 38 across an entire circumference thereof at
the radially inner portion of the cover plate 14. Thus, a distance
is assured from the portion where the cover plate 14 is slidably in
pressure contact with the thrust member 38 to a portion where the
viscous medium, which exists at the radially outward portion in the
chamber 53, splashes, and accordingly the viscous medium 54 is
restricted from leaking out. In addition, because a sliding radius
of the cover plate 14 and the thrust member 38, that is, a distance
between a center of the rotation of the cover plate 14 and of the
thrust member 38, and a portion at which the cover plate 14 and the
thrust member 38 are in contact with each other, is small,
hysteresis may be set to be small, thereby enhancing a performance
of the torque fluctuation reducing apparatus 3.
[0045] The plate 15 is an annular-shaped member and the component
member of the first main damper 3a (refer to FIGS. 1 and 2). The
plate 15 is disposed between the cover plate 14 and the cover plate
16 so as to be closely attached to the cover plate 14 and to the
cover plate 16 at a radially outward portion of the plate 15. The
plate 15 is fixed by welding to the cover plates 14, 16. Thus, the
plate 15 rotates integrally with the cover plate 14 and the cover
plate 16, and the viscous medium 54 inside the chamber 53 does not
leak out from the connection portion at which the plate 15, the
cover plate 14 and the cover plate 16 are joined to one another.
The plate 15 is arranged at the engine-side (the right side in FIG.
1) relative to the intermediate plate 18. The plate 15 includes an
accommodation portion 15a which is formed in a form of a bag for
accommodating therein the coil spring 19 and the guide member 20.
The plate 15 supports the centrifugal force of the coil spring 19
and of the guide member 20, and a component force acting in the
radial direction in a case where the coil spring 19 is compressed.
The accommodation portion 15a is configured to be in contact with
and out of contact from the coil spring 19 at circumferential end
surfaces of the accommodation portion 15a. In a case where a
torsion is not generated between the plate 15 and the cover plate
16, and the intermediate plate 18, the accommodation portion 15a is
in contact with both end portions of the coil spring 19 or the
accommodation portion 15a is positioned close to the end portions
of the coil spring 19 while leaving a slight play between the
accommodation portion 15a and the coil spring 19. In a case where
the torsion is generated between the plate 15 and the cover plate
16, and the intermediate plate 18, the accommodation portion 15a is
in contact with one of the end portions of the coil spring 19. The
plate 15 includes a through hole 15b at the accommodation portion
15a. The through hole 15b is a hole for allowing the viscous medium
54 to communicate between an inside and an outside of the
accommodation portion 15a.
[0046] The cover plate 16 serves as the first power transmission
member which is formed in an annular shape and which covers a
transmission-side (the left side in FIG. 1) of the chamber 53, and
is the component member of the first main damper 3a (refer to FIGS.
1 and 2). The cover plate 16 serves also as the first main damper
3a, and accordingly, the number of parts and components is reduced.
The cover plate 16 is closely attached to the cover plate 14 via
the plate 15, at a radially outward portion of the cover plate 16
across an entire circumference thereof, and is fixed by welding to
the plate 15 and to the cover plate 14. Thus, the cover plate 16
rotates integrally with the plate 15 and with the cover plate 14,
and the viscous medium 54 inside the chamber 53 does not leak out
from the connection portion at which the cover plate 16, the plate
15 and the cover plate 14 are joined to one another. The cover
plate 16 is arranged at the transmission-side (the left side in
FIG. 1) relative to the intermediate plate 18. The cover plate 16
includes an accommodation portion 16a which is formed in a form of
a bag for accommodating therein the coil spring 19 and the guide
member 20. The cover plate 16 supports the centrifugal force of the
coil spring 19 and of the guide member 20, and the component force
acting in the radial direction in a case where the coil spring 19
is compressed. The accommodation portion 16a is configured to be in
contact with and out of contact from the coil spring 19 at
circumferential end surfaces of the accommodation portion 16a. In a
case where the torsion is not generated between the cover plate 16
and the plate 15, and the intermediate plate 18, the accommodation
portion 16a is in contact with the end portions of the coil spring
19 or the accommodation portion 16a is positioned close to the end
portions of the coil spring 19 while leaving a slight play between
the accommodation portion 16a and the coil spring 19. In a case
where the torsion is generated between the cover plate 16 and the
plate 15, and the intermediate plate 18, the accommodation portion
16a is in contact with one of the end portions of the coil spring
19. The cover plate 16 extends radially inwardly relative to the
coil springs 19, 24, 25, 36, 46 of the main dampers 3a, 3b and the
dynamic dampers 3c, 3d, respectively. The cover plate 16, at a
radially inward portion thereof, is slidably in pressure contact
with an outer circumferential end portion of the disc spring 51
across an entire circumference thereof. Thus, a distance is assured
from the portion where the cover plate 16 is slidably in pressure
contact with the disc spring 51 to the portion where the viscous
medium, which exists at the radially outward portion in the chamber
53, splashes, and accordingly the viscous medium 54 is restricted
from leaking out. In addition, because a sliding radius of the
cover plate 16 and the disc spring 51 is small, the hysteresis may
be set to be small, thereby enhancing the performance of the torque
fluctuation reducing apparatus 3.
[0047] The inertia body 17 is an annular-shaped member which is
fixed by welding at the cover plate 14, at the surface of the cover
plate 14 which is at the engine-side (the right side in FIG. 1)
(refer to FIGS. 1 and 2).
[0048] The intermediate plate 18 is an annular-shaped member which
is disposed between the plate 15 and the cover plate 16, and is the
component member of the first main damper 3a and of the second main
damper 3b (refer to FIGS. 1 and 2). The intermediate plate 18 is
arranged at radially inwardly relative to the connection portion at
which the plate 15 and the cover plate 16 are connected to each
other, in a manner that a predetermined distance is provided
between the connection portion and the intermediate plate 18.
[0049] The intermediate plate 18 includes, at an outer
circumferential portion thereof, a window portion 18a defined by a
cut-out portion for accommodating the coil spring 19 and the guide
member 20. The window portion 18a is the component part of the
first main damper 3a. The window portion 18a is configured to be in
contact with and out of contact from the coil spring 19 at
circumferential end surfaces of the window portion 18a. In a case
where the torsion is not generated between the intermediate plate
18, and the plate 15 and the cover plate 16, the window portion 18a
is in contact with the end portions of the coil spring 19 or the
window portion 18a is positioned close to the end portions of the
coil spring 19 while leaving a slight play between the window
portion 18a and the coil spring 19. In a case where the torsion is
generated between the intermediate plate 18, and the plate 15 and
the cover plate 16, the window portion 18a is in contact with one
of the end portions of the coil spring 19. The intermediate plate
21 is fixed by means of the plural rivets 22 to the intermediate
plate 18, at a radially inward portion of the intermediate plate 18
relative to the window portion 18a, at the transmission-side (at
the left side in FIG. 1) of the intermediate plate 18. Thus, the
intermediate plate 18 and the intermediate plate 21 rotate
integrally with each other. At a radially inward portion of the
intermediate plate 18 relative to the rivets 22, the intermediate
plate 18 is arranged in a manner that a predetermined distance in
the axial direction is provided relative to the intermediate plate
21, that is, the predetermined distance is provided between the
intermediate plates 18 and 21.
[0050] The intermediate plate 18 is arranged at the engine-side (at
the right side in FIG. 1) relative to a flange portion 23a of the
hub member 23. At a radially inward portion of the intermediate
plate 18 relative to the rivets 22, the intermediate plate 18
includes a window portion 18b for accommodating the seat member 26
(i.e., a first seat member) and the coil springs 24, 25 (i.e.,
first coil springs). The window portion 18b is the component part
of the second main damper 3b. At respective circumferential end
surfaces of the window portion 18b, the window portion 18b is
configured to come into contact with and out of contact from the
seat members 26. In a case where the torsion is not generated
between the intermediate plates 18, 21 and the hub member 23, the
window portion 18b is in contact with the seat members 26 arranged
at respective ends of each of the coil springs 24, 25 or the window
portion 18b is positioned close to the seat members 26 while
leaving a slight play between the window portion 18b and the seat
members 26. The window portion 18b is in contact with one of the
seat members 26 in a case where the torsion is generated between
the intermediate plates 18, 21 and the hub member 23. At a surface
of the intermediate plate 18 on the engine-side (at the right side
in FIG. 1), the side plate 30 is fixed by means of the plural
rivets 31 to the intermediate plate 18. Thus, the intermediate
plate 18 and the side plate 30 rotate integrally with each other.
At an inner circumferential portion of the intermediate plate 18,
the intermediate plate 18 engages with the thrust member 27 so as
not to be rotatable but so as to be movable in the axial direction
relative to the thrust member 27. The intermediate plate 18 is, at
an inner circumferential end portion thereof, rotatably supported
by the hub member 23 via the thrust member 27.
[0051] The coil spring 19 is the component member of the first main
damper 3a (refer to FIGS. 1 and 2). The coil spring 19 is
accommodated in the accommodation portion 15a of the plate 15, the
accommodation portion 16a of the cover plate 16 and the window
portion 18a of the intermediate plate 18. The coil spring 19 is in
contact with the circumferential end surfaces of the respective
accommodation portions 15a, 16a and the window portion 18a. The
coil spring 19 is compressed in a case where the torsion is
generated between the plate 15 and the cover plate 16, and the
intermediate plate 18. In a case where the torsion is generated
between the plate 15 and the cover plate 16, and the intermediate
plate 18, and therefore the coil spring 19 is compressed to a
substantially minimum length thereof, the coil spring 19 serves as
a stopper for restricting the torsion between the plate 15 and the
cover plate 16, and the intermediate plate 18. The coil spring 19
is set to have a spring constant which differs from spring
constants of the coil springs 24, 25. For the coil spring 19, an
arc spring having a circular arc-shape, which is formed so as to be
expanded and compressed in a circumferential direction thereof, may
be used. Thus, a torsional angle of the first main damper 3a is set
to be large, and accordingly a torsional rigidity thereof is
reduced, which lowers a resonance rotation speed.
[0052] The guide member 20 is the component member of the first
main damper 3a. In a case where the centrifugal force works, the
guide member 20 reduces wear occurring between the accommodation
portion 15a of the plate 15 and the coil spring 19 (i.e., an arc
coil spring), and between the accommodation portion 16a of the
cover plate 16 and the coil spring 19, and guides the expansion and
compression, that is, the compression and return, of the coil
spring 19. The guide member 20 is disposed between the
accommodation portions 15a, 16a and the coil spring 19 in the
radial direction.
[0053] The intermediate plate 21 is an annular-shaped member which
is provided at the transmission-side (the left side in FIG. 1)
relative to the flange portion 23a of the hub member 23, and is the
component member of the second main damper 3b (refer to FIGS. 1 and
2). The intermediate plate 21 is, at an outer circumferential
portion thereof, fixed to the intermediate plate 18 by means of the
plural rivets 22. Thus, the intermediate plate 21 and the
intermediate plate 18 rotate integrally with each other. The
intermediate plate 21 includes a stopper portion 21a at a radially
inward portion of the intermediate plate 21 relative to the rivets
22. The stopper portion 21a is a portion which restricts the
torsion of the second main damper 3b at a predetermined angle. The
stopper portion 21a restricts the torsion of the second main damper
3b by being in contact with a stopper portion 23c of the hub member
23 in a case where the torsion is generated at the second main
damper 3b. At a radially inward portion of the intermediate plate
21 relative to the stopper portion 21a, the intermediate plate 21
is arranged in a manner that the predetermined distance in the
axial direction is provided relative to the intermediate plate 18.
At a radially inward portion of the intermediate plate 21 relative
to the rivets 22, the intermediate plate 21 includes a window
portion 21b for accommodating the seat members 26 and the coil
springs 24, 25. The window portion 21b is configured to be in
contact with and out of contact from the seat members 26 at
respective circumferential end surfaces of the window portion 21b.
In a case where the torsion is not generated between the
intermediate plates 18, 21 and the hub member 23, the window
portion 21b is in contact with the seat members 26 arranged at
respective ends of each of the coil springs 24, 25 or the window
portion 21b is positioned close to the seat members 26 while
leaving a slight play between the window portion 21b and the seat
members 26. The window portion 21b is in contact with one of the
seat members 26 in a case where the torsion is generated between
the intermediate plates 18, 21 and the hub member 23. The side
plate 41 is fixed by means of the plural rivets 42 to the
intermediate plate 21, at a surface of the intermediate plate 21 at
the transmission-side (at the left side in FIG. 1). Thus, the
intermediate plate 21 and the side plate 41 rotate integrally with
each other. At an inner circumferential portion of the intermediate
plate 21, the intermediate plate 21 engages with the thrust member
28 so as not to be rotatable and so as to be movable in the axial
direction relative to the thrust member 28. The intermediate plate
21 supports an outer circumferential end portion of the disc spring
29. The intermediate plate 21 is, at an inner circumferential end
portion thereof, rotatably supported by the hub member 23 via the
thrust member 28.
[0054] The rivet 22 is a member for fixing by staking the
intermediate plate 18 and the intermediate plate 21 to each other
(refer to FIGS. 1 and 2).
[0055] The hub member 23 is a second power transmission member
which is formed in cylindrical-shaped and outputs the rotative
power of the torque fluctuation reducing apparatus 3 toward the
rotational shaft 4, and is the component member of the second main
damper 3b (refer to FIG. 1). The hub member 23 includes the flange
portion 23a extending radially outwardly from a predetermined
portion of an outer periphery of a cylinder portion of the
cylindrical shape. The hub member 23, at an inner circumferential
surface thereof, is engaged by spline with the rotational shaft 4.
At an outer circumference of the hub member 23, the hub member 23
rotatably supports the intermediate plate 18 via the thrust member
27 and rotatably supports the intermediate plate 21 via the thrust
member 28. In addition, the hub member 23 rotatably supports the
side plate 32 and the center plate 34 via the thrust member 40 at
the outer circumference of the hub member 23, and rotatably
supports the thrust member 38. In addition, the hub member 23, at
the outer circumference thereof, rotatably supports the side plate
41 and the center plate 45 via the thrust member 48, and rotatably
supports the thrust member 50. The flange portion 23a includes a
window portion 23b for accommodating the coil springs 24, 25 and
the seat members 26. The window portion 23b is configured to come
into contact with and out of contact from the seat members 26 at
respective circumferential end surfaces of the window portion 23b.
In a case where the torsion is not generated between hub member 23
and the intermediate plates 18, 21, the window portion 23b is in
contact with the seat members 26 at the respective ends of each of
the coil springs 24, 25 or the window portion 23b is positioned
close to the seat members 26 while leaving a slight play between
the window portion 23b and the seat members 26. The window portion
23b is configured to be in contact with the seat members 26 in a
case where the torsion is generated between the hub member 23 and
the intermediate plates 18, 21. At a radially inward portion of the
flange portion 23a, at surfaces thereof in the axial direction, the
flange portion 23a is slidably held by the thrust members 27, 28 in
a sandwiched manner therebetween. The flange portion 23a includes
the stopper portion 23c at plural positions at an outer
circumferential end portion of the flange portion 23a, and each of
the stopper portions 23c protrudes radially outwardly. The stopper
portion 23c is a portion which restricts the torsion of the second
main damper 3b at the predetermined angle. The stopper portion 23c
restricts the torsion of the second main damper 3b by being in
contact with the stopper portion 21a of the intermediate plate 21
in a case where the torsion is generated at the second main damper
3b.
[0056] The coil springs 24, 25 are the component members of the
second main damper 3b (refer to FIGS. 1 and 2). The coil spring 25
is arranged inside a winding wire of the coil spring 24. The coil
springs 24, 25 are accommodated in the window portions 18b, 21b,
23b which are formed at the intermediate plates 18, 21 and the hub
member 23, respectively, and are in contact with the seat members
26 arranged at the respective ends of the coil springs 24, 25. In a
case where the intermediate plates 18, 21 and the hub member 23
rotate relative to each other, the coil springs 24, are compressed
and absorb rotational fluctuation.
[0057] The seat members 26 are the component members of the second
main damper 3b (refer to FIGS. 1 and 2). The seat members 26 are
accommodated in the window portions 18b, 21b, 23b which are formed
at the intermediate plates 18, 21 and the hub member 23,
respectively, in a manner that each of the seat members 26 is
arranged between the circumferential end surfaces of the respective
window portions 18b, 21b, 23b and corresponding end portions of
each of the coil springs 24, 25. The seat members 26 may be made of
resin in order to reduce the wear of the coil springs 24, 25, the
intermediate plates 18, 21 and the hub member 23.
[0058] The thrust member 27 is an annular-shaped member arranged
between the intermediate plate 18 and the hub member 23 (refer to
FIG. 1). The thrust member 27 is arranged between the intermediate
plate 18 and the flange portion 23a in the axial direction. The
thrust member 27 engages with the intermediate plate 18 so as not
to be rotatable and so as to be movable in the axial direction
relative to the intermediate plate 18. The thrust member 27 is
slidably in pressure contact with the flange portion 23a. The
thrust member 27 is interposed also between the intermediate plate
18 and the hub member 23 in the radial direction, thereby serving
as a slide bearing (a bush) for rotatably supporting the
intermediate plate 18 at the hub member 23.
[0059] The thrust member 28 is an annular-shaped member arranged
between the intermediate plate 21 and the hub member 23 (refer to
FIG. 1). The thrust member 28 is arranged between the disc spring
29 and the flange portion 23a in the axial direction. The thrust
member 28 engages with the intermediate plate 21 so as not to be
rotatable but so as to be movable in the axial direction relative
to the intermediate plate 21. The thrust member 28 is biased or
pushed by the disc spring 29 toward the flange portion 23a, and is
slidably in pressure contact with the flange portion 23a. The
thrust member 28 is interposed also between the intermediate plate
21 and the hub member 23 in the radial direction, thereby serving
as a slide bearing (a bush) for rotatably supporting the
intermediate plate 21 at the hub member 23.
[0060] The disc spring 29 is a disc-shaped spring which is arranged
between the thrust member 28 and the intermediate plate 21, and
biases or pushes the thrust member 28 toward the flange portion 23a
(refer to FIG. 1).
[0061] The side plate 30 is an annular-shaped member which is
arranged at the transmission-side (the left side in FIG. 1)
relative to the center plate 34, and is the component member of the
first dynamic damper 3c. The side plate 30 is arranged in a manner
that a predetermined distance is provided relative to the side
plate 32 in the axial direction. The side plate 30 is, at an outer
circumferential portion thereof, fixed to the side plate 32 by
means of the rivet 33 to be integrally with the side plate 32. The
side plate 30 is, at a radially inward portion thereof relative to
the rivet 33, fixed to the intermediate plate 18 by means of the
rivet 31. Thus, the side plate 30 and the intermediate plate 18
rotate integrally with each other. The side plate 30 includes a
window portion 30a for accommodating the seat members 37 (i.e., a
second seat member) and the coil spring 36 (i.e., a second coil
spring) at a radially inward portion of the side plate 30 relative
to the rivet 33, and circumferential end surfaces of the window
portion 30a are configured to be in contact with and out of contact
from the respective seat members 37. The side plate 30 is, at a
radially inward portion thereof relative to the window portion 30a,
in pressure contact with the thrust member 40 so as to be rotatable
relative to the thrust member 40.
[0062] The rivet 31 is a member for fixing the side plate 30 to the
intermediate plate 18 (refer to FIG. 1).
[0063] The side plate 32 is an annular-shaped member arranged at
the engine-side (the right side in FIG. 1) relative to the center
plate 34, and is the component member of the first dynamic damper
3c. The side plate 32 is arranged in a manner that a predetermined
distance is provided in the axial direction relative to the side
plate 30. The side plate 32 is, at an outer circumferential portion
thereof, fixed to the side plate 30 to be integral with the side
plate 30 by means of the rivet 33. Thus, the side plate 32 and the
side plate 30 rotate integrally with each other. The side plate 32
includes a window portion 32a for accommodating the seat members 37
and the coil spring 36 at a radially inward portion of the side
plate 32 relative to the rivet 33. Circumferential end surfaces of
the window portion 32a are in contract with the corresponding seat
members 37 so as to come into contact with and come out of contact
from the seat members 37. The side plate 32 is, at a radially
inward portion thereof relative to the window portion 32a, slidably
held in a sandwiched manner between the thrust member 38 and the
thrust member 39. The side plate 32 is, at an inner circumferential
portion thereof, rotatably supported via the thrust member 40 by
the hub member 23.
[0064] The rivet 33 is a member for integrally connecting the side
plate 30 and the side plate 32 with each other (refer to FIG. 1).
The side plate 30 is fixed at one end of the rivet 33 by staking
and the side plate 32 is fixed at the other end of the rivet 33 by
staking. An intermediate portion of the rivet 33 is inserted
through a through hole 34b of the center plate 34. The rivet 33
restricts the torsion of the first dynamic damper 3c at a
predetermined angle. The rivet 33 restricts the torsion of the
first dynamic damper 3c by being in contact with a circumferential
end surface of the through hole 34b in a case where the torsion is
generated at the first dynamic damper 3c.
[0065] The center plate 34 is an annular member arranged between
the side plate 30 and the side plate 32, and is the component
member of the first dynamic damper 3c (refer to FIGS. 1, 2 and 3).
The center plate 34 includes, at an outer circumferential portion
thereof, the inertia body portion 34d which is arranged to be
extended to a radially outer side relative to the side plates 30,
32. The inertia body portion 34d is a portion which serves as the
inertia of the first dynamic damper 3c. The inertia body 35 is
fixed by welding or with a rivet to the inertia body portion 34d.
Thus, the center plate 34 and the inertia body 35 rotate integrally
with each other. The inertia body portion 34d includes a through
hole 34c (i.e., a through hole). The through hole 34c is for
restricting the movement of the inertia of the first dynamic damper
3c by restricting movement of the center plate 34 in the viscous
medium 54. The center plate 34 includes, at a radially inward
portion thereof relative to the inertia body portion 34d, the
through hole 34b. The rivet 33 is inserted through the through hole
34b. The through hole 34b restricts the torsion of the first
dynamic damper 3c at the predetermined angle. The through hole 34b
restricts the torsion of the first dynamic damper 3c in a manner
that the circumferential end surface of the through hole 34b is in
contact with the rivet 33 in a case where the torsion is generated
at the first dynamic damper 3c. The center plate 34 includes a
window portion 34a for accommodating the coil spring 36 and the
seat members 37. The window portion 34a is configured to come in
contact with and out of contact from the seat members 37 at
respective circumferential end surfaces of the window portion 34a.
In a case where a torsion is not generated between the center plate
34 and the side plates 30, 32, the window portion 34a is in contact
with the seat members 37 arranged at both sides of the coil spring
36 or the window portion 34a is positioned close to the seat
members 37 while leaving a slight play between the window portion
34a and the seat members 37. In a case where the torsion is
generated between the center plate 34 and the side plates 30, 32,
the window portion 34a is in contact with one of the seat members
37. The center plate 34 is slidably held between the thrust member
40 and the thrust member 39 in a sandwiched manner in the axial
direction. The center plate 34 is, at an inner circumferential end
portion thereof, rotatably supported via the thrust member 40 at
the hub member 23.
[0066] The inertia body 35 is an annular member serving as the
inertia of the first dynamic damper 3c (refer to FIGS. 1, 2 and 3).
The inertia body 35 is fixed by welding or with a rivet to the
inertia body portion 34d of the center plate 34. Thus, the inertia
body 35 and the center plate 34 rotate integrally with each other.
The inertia body 35 includes a through hole 35a (i.e., the through
hole). The through hole 35a is for restricting the movement of the
inertia of the first dynamic damper 3c by restricting movement of
the inertia body 35 in the viscous medium 54.
[0067] The coil spring 36 is the component member of the first
dynamic damper 3c (refer to FIGS. 1 and 2). The coil spring 36 is
accommodated in the window portions 30a, 32a and 34a which are
formed at the side plates 30, 32 and the center plate 34,
respectively, and is in contact with the seat members 37 arranged
at the respective sides of the window portions 30a, 32a and 34a.
The coil spring 36 is for setting the resonance frequency of the
first dynamic damper 3c by means of a combination of the coil
spring 36, and the inertia of the center plate 34 and of the
inertia body 35.
[0068] The seat members 37 are the component members of the first
dynamic damper 3c (refer to FIGS. 1 and 2). The seat members 37 are
accommodated in the window portions 30a, 32a and 34a which are
formed at the side plates 30, 32 and the center plate 34,
respectively, in a manner that each of the seat members 37 is
disposed between the circumferential end surfaces of the respective
window portions 30a, 32a, 34a and a corresponding end portion of
the coil spring 36. The seat members 37 may be made of resin in
order to reduce the wear of the coil spring 36, the side plates 30,
32 and the center plate 34.
[0069] The thrust member 38 is an annular member rotatably arranged
at the outer circumference of the hub member 23 (refer to FIG. 1).
The thrust member 38 is arranged between the cover plate 14 and the
side plate 32 in the axial direction. The thrust member 38 is
slidably in pressure contact with the cover plate 14, and is
slidably in pressure contact with the side plate 32. The thrust
member 38 serves as a seal member sealing a clearance between the
cover plate 14 and the hub member 23.
[0070] The thrust member 39 is an annular member rotatably arranged
at an outer circumference of the thrust member 40 (refer to FIG.
1). The thrust member 39 is arranged between the center plate 34
and the side plate 32 in the axial direction. The thrust member 39
is slidably in pressure contact with the center plate 34, and is
slidably in pressure contact with the side plate 32.
[0071] The thrust member 40 is an annular member arranged between
the center plate 34 and the hub member 23 (refer to FIG. 1). The
thrust member 40 is arranged between the center plate 34 and the
side plate 30 in the axial direction. The thrust member 40 is
slidably in pressure contact with the center plate 34, and is
slidably in pressure contact with the side plate 30. The thrust
member 40 is interposed also between the center plate 34 and the
side plate 32, and the hub member 23 in the radial direction,
thereby serving as a slide bearing (a bush) for rotatably
supporting the center plate 34 and the side plate 32 at the hub
member 23.
[0072] The side plate 41 is an annular member arranged at the
engine-side (the right side in FIG. 1) relative to the center plate
45, and is the component member of the second dynamic damper 3d.
The side plate 41 is arranged in a manner that a predetermined
distance in the axial direction is provided relative to the side
plate 43. The side plate 41 is, at an outer circumferential portion
thereof, fixed to the side plate 43 to be integrally with the side
plate 43 by means of the rivet 44. The side plate 41 is, at a
radially inward portion thereof relative to the rivet 44, fixed by
means of the rivet 42 to the intermediate plate 21. Thus, the side
plate 41 and the intermediate plate 21 rotate integrally with each
other. The side plate 41 includes, at a radially inward portion
thereof relative to the rivet 44, a window portion 41a for
accommodating the seat members 47 (i.e., the second seat members)
and the coil spring 46 (i.e., the second coil spring), and
circumferential end surfaces of the window portion 41a are
configured to be in contact with and out of contact from the
respective seat members 47. The side plate 41 is, at a radially
inward portion thereof relative to the window portion 41a, in
pressure contact with the thrust member 48 so as to be rotatable
relative to the thrust member 48.
[0073] The rivet 42 is a member for fixing the side plate 41 to the
intermediate plate 21 (refer to FIG. 1).
[0074] The side plate 43 is an annular member arranged at the
transmission-side (the left side in FIG. 1) relative to the center
plate 45, and is the component member of the second dynamic damper
3d. The side plate 43 is arranged in a manner that the
predetermined distance in the axial direction is provided relative
to the side plate 41. The side plate 43 is, at an outer
circumferential portion thereof, fixed to the side plate 41 to be
integrally with the side plate 41 by means of the rivet 44. Thus,
the side plate 43 and the side plate 41 rotate integrally with each
other. The side plate 43 includes, at a radially inward portion
thereof relative to the rivet 44, a window portion 43a for
accommodating the seat members 47 and the coil spring 46, and
circumferential end surfaces of the window portion 43a are
configured to be in contact with and out of contact from the
respective seat members 47. The side plate 43 is, at a radially
inward portion thereof relative to the window portion 43a,
rotatably held between the thrust member 49 and the thrust member
50 in a sandwiched manner therebetween.
[0075] The rivet 44 is a member for connecting the side plate 41
and the side plate 43 so that the side plate 41 and the side plate
43 are integral with each other (refer to FIG. 1). The side plate
41 is fixed at one end of the rivet 44 by staking and the side
plate 43 is fixed at the other end of the rivet 44 by staking. An
intermediate portion of the rivet 44 is inserted through a through
hole 45b of the center plate 45. The rivet 44 restricts the torsion
of the second dynamic damper 3d at a predetermined angle. The rivet
44 restricts the torsion of the second dynamic damper 3d by being
in contact with a circumferential end surface of the through hole
45b in a case where the torsion is generated at the second dynamic
damper 3d.
[0076] The center plate 45 is an annular member arranged between
the side plate 41 and the side plate 43, and is the component
member of the second dynamic damper 3d (refer to FIG. 1). The
center plate 45 includes, at an outer circumferential portion
thereof, the inertia body portion 45c which is arranged to be
extended to a radially outer side relative to the side plates 41,
43. The inertia body portion 45c is a portion which serves as an
inertia of the second dynamic damper 3d. The center plate 45
includes, at a radially inward portion thereof relative to the
inertia body portion 45c, the through hole 45b. The rivet 44 is
inserted through the through hole 45b. The through hole 45b
restricts the torsion of the second dynamic damper 3d at the
predetermined angle. The through hole 45b restricts the torsion of
the second dynamic damper 3d in a manner that the circumferential
end surface of the through hole 45b is in contact with the rivet 44
in a case where the torsion is generated at the second dynamic
damper 3d. The center plate 45 includes a window portion 45a for
accommodating the coil spring 46 and the seat members 47. At
respective circumferential end surfaces of the window portion 45a,
the window portion 45a is configured to be in contact with and out
of contact from the seat members 47. In a case where a torsion is
not generated between the center plate 45 and the side plates 41,
43, the window portion 45a is in contact with the seat members 47
arranged at respective ends of the coil spring 46 or the window
portion 45a is positioned close to the seat members 47 while
leaving a slight play between the window portion 45a and the seat
members 47. In a case where the torsion is generated between the
center plate 45 and the side plates 41, 43, the window portion 45a
is in contact with one of the seat members 47. The center plate 45
is slidably held between the thrust member 48 and the thrust member
49 in a sandwiched manner in the axial direction. The center plate
45 is, at an inner circumferential end portion thereof, rotatably
supported via the thrust member 48 at the hub member 23.
[0077] The coil spring 46 is the component member of the second
dynamic damper 3d (refer to FIGS. 1 and 2). The coil spring 46 is
accommodated in the window portions 41a, 43a, 45a which are formed
at the side plates 41, 43 and the center plate 45, respectively,
and the coil spring 46 is in contact with the seat members 47
arranged at the respective sides of the coil spring 46. The coil
spring 46 is for setting the resonance frequency of the second
dynamic damper 3d by means of a combination of the coil spring 46
and an inertia of the center plate 45.
[0078] The seat members 47 are the component members of the second
dynamic damper 3d (refer to FIGS. 1 and 2). The seat members 47 are
accommodated in the window portions 41a, 43a, 45a which are formed
at the side plates 41, 43 and the center plate 45, respectively, in
a manner that each of the seat members 47 is disposed between the
circumferential end surfaces of the respective window portions 41a,
43a, 45a and a corresponding end portion of the coil spring 46. The
seat members 47 may be made of resin in order to reduce the wear of
the coil spring 46, the side plates 41, 43 and the center plate
45.
[0079] The thrust member 48 is an annular member rotatably arranged
between the center plate 45 and the hub member 23 (refer to FIG.
1). The thrust member 48 is arranged between the center plate 45
and the side plate 41 in the axial direction. The thrust member 48
is slidably in pressure contact with the center plate 45, and is
slidably in pressure contact with the side plate 41. The thrust
member 48 is interposed also between the center plate 45 and the
side plate 41, and the hub member 23 in the radial direction, and
serves as a slide bearing (a bush) for rotatably supporting the
center plate 45 and the side plate 41 at the hub member 23.
[0080] The thrust member 49 is an annular member rotatably arranged
at an outer circumference of the thrust member 48 (refer to FIG.
1). The thrust member 49 is arranged between the center plate 45
and the side plate 43 in the axial direction. The thrust member 49
is slidably in pressure contact with the center plate 45, and is
slidably in pressure contact with the side plate 43.
[0081] The thrust member 50 is an annular member rotatably arranged
at the outer circumference of the hub member 23 (refer to FIG. 1).
The thrust member 50 is arranged between the disc spring 51 and the
side plate 43 in the axial direction. The thrust member 50 is
biased or pushed by the disc spring 51 toward the side plate 43,
and is slidably in pressure contact with the side plate 43. The
thrust member 50, in combination with the disc spring 51, serves as
the seal member sealing a clearance between the cover plate 16 and
the hub member 23.
[0082] The disc spring 51 is a disc-shaped spring which is arranged
between the thrust member 50 and the cover plate 16, and biases or
pushes the thrust member 50 toward the side plate 43 (refer to FIG.
1). An inner circumferential end portion of the disc spring 51 is
in contact with the thrust member 50 across the entire
circumference thereof, and an outer circumferential end portion of
the disc spring 51 is in contact with the cover plate 16 across the
entire circumference thereof. The disc spring 51 covers or seals a
clearance between the thrust member 50 and the cover plate 16 so
that the viscous medium 54 is enclosed in the chamber 53. The disc
spring 51, in combination with the thrust member 50, serves as the
seal member sealing the clearance between the cover plate 16 and
the hub member 23.
[0083] Next, an operation of the torque fluctuation reducing
apparatus according to the first embodiment will be explained with
reference to the drawings (refer to FIG. 5).
[0084] In a case where a dynamic damper is provided at a general
torque fluctuation reducing apparatus including a main damper
provided on a power transmission path between an engine and a
transmission, a damping performance improves at an aimed resonance
point, that is, the resonance point at which the damping
performance is intended to be improved (refer to "an absorption
portion" in FIG. 5). However, "a contradiction portion", at which
the damping performance is impaired, exists at rotation speeds that
precede and follow the absorption portion.
[0085] At a torque fluctuation reducing apparatus including two
main dampers provided in series with each other on a power
transmission path between an engine and a transmission, in a case
where a dynamic damper is provided at a first-order plate (which
corresponds to the cover plate 14, the plate 15 and the cover plate
16 in FIG. 1) arranged before, in terms of the order in which the
power is transmitted, the main damper at an engine-side, the
dynamic damper needs to be large in size because the vibrations
inputted to the dynamic damper are large.
[0086] In addition, in a case where the dynamic damper is provided
at a third-order plate (which corresponds to the hub member 23 in
FIG. 1) arranged after, in terms of the order in which the power is
transmitted, the main damper provided at a transmission-side, small
effects are obtained because the vibrations have been reduced at
the third-order plate by the main dampers 3a, 3b that are arranged
in series with each other.
[0087] On the other hand, in a case where the dynamic damper is
provided at a second-order plate (which corresponds to the
intermediate plate 18, the intermediate plate 21 in FIG. 1)
arranged between the two main dampers as explained in the first
embodiment disclosed here, the damping performance improves
compared to the cases where the dynamic damper is provided at the
first-order plate and/or third-order plate.
[0088] According to the first embodiment, damping effects are
increased by providing the dynamic dampers 3c, 3d at the
intermediate plates 18, 21 arranged between the main dampers 3a,
3b. In addition, according to the first embodiment, the wear of
each of the dampers is restricted by enclosing the viscous medium
54 in the chamber 53. Further, according to the first embodiment,
an amount that the inertia body (the inertia body portion 34d, the
inertia body 35) of the first dynamic damper 3c and the viscous
medium 54 are in contact with each other, that is, a surface area
of the inertia body of the dynamic damper 3c, which is in contact
with the viscous medium 54, is controlled by enclosing the viscous
medium 54 in the part of the chamber 53, and consequently an
optimum damping is obtained.
[0089] A torque fluctuation reducing apparatus according to a
second embodiment will be explained with reference to the drawings
(refer to FIGS. 6A and 6B).
[0090] The second embodiment is a variation of the first
embodiment. According to the second embodiment, the inertia body
(corresponding to the inertia body 35 in FIG. 1) is not provided at
the center plate 34 of the first dynamic damper (corresponding to
the first dynamic damper 3c in FIG. 1) and a
radially-recessed-and-protruding portion 34e (i.e., a
recessed-and-protruding portion) is provided at an outer
circumferential end surface of the inertia body portion 34d of the
center plate 34. The radially-recessed-and-protruding portion 34e
is formed in a teeth configuration (a gear configuration) which
includes recess and protrusion in the radial direction. The
radially-recessed-and-protruding portion 34e is set to be immersed
in or be in contact with the viscous medium (corresponding to the
viscous medium 54 in FIG. 1) in the chamber (corresponding to the
chamber 53 in FIG. 1) so that a resistance occurring when the
inertia body portion 34d moves in the viscous medium (corresponding
to the viscous medium 54 in FIG. 1) is increased. Other structures
and configurations of the second embodiment are identical to those
of the first embodiment.
[0091] According to the second embodiment, advantages likewise the
first embodiment are attained. In addition, a vibration damping
performance is improved by adjusting or optimizing the resistance
of the inertia body portion 34d by providing the
radially-recessed-and-protruding portion 34e, and thus noises for
suppressing the movement of the inertia of the first dynamic damper
(corresponding to the first dynamic damper 3c in FIG. 1) are
restricted from occurring.
[0092] A torque fluctuation reducing apparatus according to a third
embodiment will be explained with reference to the drawings (refer
to FIGS. 7A and 7B).
[0093] The third embodiment is a variation of the first embodiment.
According to the third embodiment, the inertia body (corresponding
to the inertia body 35 in FIG. 1) is not provided at the center
plate 34 of the first dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1) and an axially-recessed-and-protruding
portion 34f (i.e., the recessed-and-protruding portion) which
includes recess and protrusion in the axial direction is provided
at the inertia body portion 34d of the center plate 34. In this
embodiment, plural axially-recessed-and-protruding portions 34f are
provided. The axially-recessed-and-protruding portion 34f is
configured by pressing and/or punching so that the protrusion is
formed at a surface of one side of the inertia body portion 34d and
the recess is formed at a surface of the opposite side of the
inertia body portion 34d. The axially-recessed-and-protruding
portion 34f is set to be immersed in or be in contact with the
viscous medium (corresponding to the viscous medium 54 in FIG. 1)
in the chamber (corresponding to the chamber 53 in FIG. 1) so that
the resistance occurring when the inertia body portion 34d moves in
the viscous medium (corresponding to the viscous medium 54 in FIG.
1) is increased. Other structures and configurations of the third
embodiment are identical to those of the first embodiment.
[0094] According to the third embodiment, the advantages likewise
the first embodiment are attained. In addition, the vibration
damping performance is improved by adjusting or optimizing the
resistance of the inertia body portion 34d by providing the
axially-recessed-and-protruding portion 34f, and thus the noises
for suppressing the movement of the inertia of the first dynamic
damper (corresponding to the first dynamic damper 3c in FIG. 1) are
restricted from occurring.
[0095] A torque fluctuation reducing apparatus according to a
fourth embodiment will be explained with reference to the drawings
(refer to FIGS. 8A and 8B).
[0096] The fourth embodiment is a variation of the first
embodiment. According to the fourth embodiment, the inertia body
(corresponding to the inertia body 35 in FIG. 1) is not provided at
the center plate 34 of the first dynamic damper (corresponding to
the first dynamic damper 3c in FIG. 1) and the through hole 34c
formed to pass through the inertia body portion 34d in the axial
direction is provided at the inertia body portion 34d of the center
plate 34. In this embodiment, plural through holes 34c are
provided. The through hole 34c is set to be immersed in or be in
contact with the viscous medium (corresponding to the viscous
medium 54 in FIG. 1) in the chamber (corresponding to the chamber
53 in FIG. 1) so that the resistance occurring when the inertia
body portion 34d moves in the viscous medium (corresponding to the
viscous medium 54 in FIG. 1) is increased. Other structures and
configurations of the fourth embodiment are identical to those of
the first embodiment.
[0097] According to the fourth embodiment, the advantages likewise
the first embodiment are attained. In addition, the vibration
damping performance is improved by adjusting or optimizing the
resistance of the inertia body portion 34d by providing the through
hole 34c, and thus the noises for suppressing the movement of the
inertia of the first dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1) are restricted from occurring.
[0098] A torque fluctuation reducing apparatus according to a fifth
embodiment will be explained with reference to the drawings (refer
to FIGS. 9A, 9B and 9C).
[0099] The fifth embodiment is a variation of the first embodiment.
According to the fifth embodiment, instead of providing the inertia
body (corresponding to the inertia body 35 in FIG. 1) at the center
plate 34 of the first dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1), an inertia body block 52 (i.e., a
block) is provided at the center plate 34. In this embodiment,
plural inertia body blocks 52 are provided. The inertia body block
52 is fixed by welding or with a rivet to the inertia body portion
34d of the center plate 34. The inertia body block 52 is set to be
immersed in or be in contact with the viscous medium (corresponding
to the viscous medium 54 in FIG. 1) in the chamber (corresponding
to the chamber 53 in FIG. 1) so that the resistance occurring when
the inertia body portion 34d moves in the viscous medium
(corresponding to the viscous medium 54 in FIG. 1) is increased.
The inertia body block 52 may be provided with, for example, a fin
(a protrusion, a bent portion or the like) which serves as a
resistance against the viscous medium (corresponding to the viscous
medium 54 in FIG. 1). Other structures and configurations of the
fifth embodiment are identical to those of the first
embodiment.
[0100] According to the fifth embodiment, the advantages likewise
the first embodiment are attained. In addition, the vibration
damping performance is improved by adjusting or optimizing the
resistance of the inertia body portion 34d by providing the inertia
body block 52, and thus the noises for suppressing the movement of
the inertia of the first dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1) are restricted from occurring.
[0101] A torque fluctuation reducing apparatus according to a sixth
embodiment will be explained with reference to the drawings (refer
to FIGS. 10A, 10B, 10C and 10D).
[0102] The sixth embodiment is a variation of the first embodiment.
According to the sixth embodiment, the inertia body (corresponding
to the inertia body 35 in FIG. 1) is not provided at the center
plate 34 of the first dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1) and a corrugated portion 34g (134g)
which is formed in the corrugated shape in the axial direction at
the inertia body portion 34d of the center plate 34. The corrugated
portion 34g (134g) is set to be immersed in or be in contact with
the viscous medium (corresponding to the viscous medium 54 in FIG.
1) in the chamber (corresponding to the chamber 53 in FIG. 1) so
that the resistance occurring when the inertia body portion 34d
moves in the viscous medium (corresponding to the viscous medium 54
in FIG. 1) is increased. Other structures and configurations of the
sixth embodiment are identical to those of the first
embodiment.
[0103] According to the sixth embodiment, the advantages likewise
the first embodiment are attained. In addition, the vibration
damping performance is improved by adjusting or optimizing the
resistance of the inertia body portion 34d by providing the
corrugated portion 34g (134g), and thus the noises for suppressing
the movement of the inertia of the first dynamic damper
(corresponding to the first dynamic damper 3c in FIG. 1) are
restricted from occurring.
[0104] A torque fluctuation reducing apparatus according to a
seventh embodiment will be explained with reference to the drawings
(refer to FIGS. 11A and 11B).
[0105] The seventh embodiment is a variation of the first
embodiment. According to the seventh embodiment, the inertia body
(corresponding to the inertia body 35 in FIG. 1) is not provided at
the center plate 34 of the first dynamic damper (corresponding to
the first dynamic damper 3c in FIG. 1) and a recessed portion 34h
recessed in the axial direction is provided at the inertia body
portion 34d of the center plate 34. In this embodiment, plural
recessed portions 34h are provided. In the first to sixth
embodiments, the resistance of the inertia body portion 34d is
increased against the viscous medium (corresponding to the viscous
medium 54 in FIG. 1). In contrast, the recessed portion 34h
according to the seventh embodiment is for reducing the resistance
against the viscous medium (corresponding to the viscous medium 54
in FIG. 1), and thus for allowing the inertia body portion 34d to
move easily. The recessed portions 34h are formed on both surfaces
of the inertia body portion 34d and are set to be immersed in or be
in contact with the viscous medium (corresponding to the viscous
medium 54 in FIG. 1) in the chamber (corresponding to the chamber
53 in FIG. 1). Other structures and configurations of the seventh
embodiment are identical to those of the first embodiment. The
recessed portions 34h of the seventh embodiment may be used in
combination with any one or more of the first to sixth
embodiments.
[0106] According to the seventh embodiment, the advantages likewise
the first embodiment are attained. In addition, an influence of the
viscous medium (corresponding to the viscous medium 54 in FIG. 1)
is reduced by the recessed portions 34h, and an original or
intended damping performance is ensured.
[0107] In the aforementioned embodiments, the engine is used as the
drive source, however, the drive source may be a motor.
[0108] Within a range of the whole disclosure (including a scope of
the claims, and the drawings) and on the basis of the basic
technical ideas thereof, the aforementioned embodiments may be
changed and/or adjusted. In addition, within a range of the scope
of the claims of this disclosure, various combinations and
selections of the elements disclosed here (including, for example,
the elements of the claims, the elements of the embodiments, the
elements in the drawings) are possible. That is, this disclosure
includes various changes and modifications that one skilled in the
art will achieve in accordance with the whole disclosure including
the scope of the claims, the drawings, and the technical idea.
[0109] According to the aforementioned embodiments, the torque
fluctuation reducing apparatus 3 includes the first main damper 3a
provided on the power transmission path between the engine 1 and
the transmission 7, and reducing, by using the elastic force, the
fluctuation torque generated between the engine 1 and the
transmission 7, the second main damper 3b provided at the
transmission-side relative to the first main damper 3a to be in
series with the first main damper 3a on the power transmission
path, and reducing, by using the elastic force, the fluctuation
torque generated between the engine 1 and the transmission 7, the
second main damper 3b including the vibration damping property
which is different from the vibration damping property of the first
main damper 3a, the first and second dynamic dampers 3c, 3d
provided on the power transmission path between the first main
damper 3a and the second main damper 3b, and restricting the
vibration at the specific resonance point of the drive system on
the power transmission path by using the inertia body portion 34d,
the inertia body 35, the inertia body portion 45c and the elastic
force, the chamber 53 accommodating the first main damper 3a and
the second main damper 3b and the first and second dynamic dampers
3c, 3d, and a viscous medium 54 enclosed in the part of the chamber
53.
[0110] According to the above-described configuration, the damping
effects are increased by providing the first and second dynamic
dampers 3c, 3d on the power transmission path between the first
main damper 3a and the second main damper 3b. In addition,
according to the above-described configuration, the wear of each of
the dampers is restricted by enclosing the viscous medium 54 in the
chamber 53. In addition, according to the above-described
configuration, the amount that the inertia body portion 34d, the
inertia body 35, the inertia body portion 45c of the first and
second dynamic dampers 3c, 3d, and the viscous medium 54 are in
contact with each other is controlled by enclosing the viscous
medium 54 in the part of the chamber 53, and therefore the most
appropriate damping is obtained even in a case where the dynamic
damper is used in a viscous medium which does not circulate.
[0111] According to the aforementioned embodiments, the first main
damper 3a is arranged radially outwardly relative to the second
main damper 3b.
[0112] According to the above-described configuration, the space of
the apparatus in the axial direction may be reduced.
[0113] According to the aforementioned embodiments, the first main
damper 3a is set to be immersed in the viscous medium 54
accumulating at the radially outward portion in the chamber 53 when
the torque fluctuation reducing apparatus 3 rotates.
[0114] According to the above-described configuration, the
component members of the first main damper 3a are restricted from
wearing.
[0115] According to the aforementioned embodiments, the first main
damper 3a includes the coil spring 19 which is formed in the
circular arc-shape and which reduces the fluctuation torque
generated between the engine 1 and the transmission 7.
[0116] According to the above-described configuration, the
torsional angle of the first main damper 3a is set to be large, and
accordingly the torsional rigidity thereof is reduced, which lowers
the resonance rotation speed.
[0117] According to the aforementioned embodiments, the torque
fluctuation reducing apparatus 3 further includes the cover plates
14, 16 which cover the chamber 53, the cover plate 14, 16 serve as
the first power transmission members on the power transmission path
at the engine-side relative to the first main damper 3a, and serve
as part of the component member of the first main damper 3a.
[0118] According to the above-described configuration, the number
of parts and components of the torque fluctuation reducing
apparatus 3 is reduced.
[0119] According to the aforementioned embodiments, the torque
fluctuation reducing apparatus 3 further includes the thrust member
38, the thrust member 50, the disc spring 51 which seal the
clearance between the hub member 23 on the power transmission path
at the transmission-side relative to the second main damper 3b, and
the cover plates 14, 16, wherein each of the cover plates 14, 16 is
formed in the annular shape and is extended radially inwardly
relative to the first main damper 3a and the second main damper 3b,
and the first and second dynamic dampers 3c, 3d.
[0120] According to the above-described configuration, the distance
is assured from the portion where the cover plate 16 is slidably in
pressure contact with the disc spring 51 to the portion where the
viscous medium, which exists at the radially outward portion in the
chamber 53, splashes. Accordingly the viscous medium 54 is
restricted from leaking out. In addition, because the sliding
radius of the cover plate 16 and the disc spring 51 is small, the
hysteresis may be set to be small, thereby enhancing the
performance of the torque fluctuation reducing apparatus 3.
[0121] According to the aforementioned embodiments, the second main
damper 3b includes the coil springs 24, 25 for reducing the
fluctuation torque generated between the engine 1 and the
transmission 7, and the seat member 26 made of the resin and
arranged at each end of the coil springs 24, 25, and the first and
second dynamic dampers 3c, 3d include the coil springs 36, 46 which
are for restricting the vibration at the specific resonance point
of the rotative power from the engine 1, and the seat members 37,
47 made of the resin and arranged at each end of the coil springs
36, 46.
[0122] According to the above-described configuration, by arranging
the seat member 26 made of the resin, the wear of the coil springs
24, 25 is reduced. In addition, by arranging the seat members 37,
47 made of the resin, the wear of the coil spring 36 is
reduced.
[0123] According to the aforementioned embodiments, the first and
second dynamic dampers 3c, 3d are provided at the respective
positions on the power transmission path between the first main
damper 3a and the second main damper 3b in a manner that the first
and second dynamic dampers 3c, 3d are parallel to each other on the
power transmission path.
[0124] According to the aforementioned embodiments, each of the
first and second dynamic dampers 3c, 3d includes the different
resonance frequency from each other.
[0125] According to the aforementioned embodiments, one or both of
the elastic force, and the inertia body portion 34d, the inertia
body 35, the inertia body portion 45c, of the first and second
dynamic dampers 3c, 3d is different from each other.
[0126] According to the aforementioned embodiments, one of the
first and second dynamic dampers 3c, 3d is arranged at one side and
the rest of the first and second dynamic dampers 3c, 3d is arranged
at the other side in the axial direction of the torque fluctuation
reducing apparatus 3 relative to the first main damper 3a and the
second main damper 3b.
[0127] According to the above-described configurations, the
vibrations may be restricted at the resonance points of the plural
systems because the characteristic properties of the first and
second dynamic dampers 3c, 3d are different from each other. In
addition, because one of the first and second dynamic dampers 3c,
3d is arranged at one side and the rest of the first and second
dynamic dampers 3c, 3d is arranged at the other side in the axial
direction of the torque fluctuation reducing apparatus 3 relative
to the first main damper 3a and the second main damper 3b, the
forces applied to the first and second main dampers 3a, 3b are
well-balanced, which is favorable to the strength of the
apparatus.
[0128] According to the aforementioned embodiments, the part of the
inertia body portion 34d, the inertia body 35, the inertia body
portion 45c of at least one of the first and second dynamic dampers
3c, 3d is set to be immersed in the viscous medium 54 accumulating
at the radially outward portion in the chamber 53 when the torque
fluctuation reducing apparatus 3 rotates.
[0129] According to the above-described configuration, by
optimizing or adjusting the resistance of the inertia body portion
34d, the inertia body 35 or the inertia body portion 45c of the
dynamic damper, the abnormal noises for restraining the movement of
the inertia body portion 34d, the inertia body 35 or the inertia
body portion 45c are restricted.
[0130] According to the aforementioned embodiments, the inertia
body portion 34d and the inertia body 35, the part of which is
immersed in the viscous medium 54 when the torque fluctuation
reducing apparatus 3 rotates, includes the
radially-recessed-and-protruding portion 34e, the
axially-recessed-and-protruding portion 34f, the through holes 34c,
35a or the corrugated portion 34g, 134g which increases the
resistance when the inertia body portion 34d, 35 moves in the
viscous medium 54.
[0131] According to the above-described configuration, the
vibration damping performance is improved by adjusting or
optimizing the resistance of the inertia body portion 34d and the
inertia body 35, and thus the abnormal noises for suppressing the
movement of the inertia body portion 34d and the inertia body 35 of
the dynamic damper (corresponding to the first dynamic damper 3c in
FIG. 1) are restricted from occurring.
[0132] According to the aforementioned embodiments, the inertia
body portion 34d, the part of which is immersed in the viscous
medium 54 when the torque fluctuation reducing apparatus 3 rotates,
is provided with the inertia body block 52 which increases the
resistance when the inertia body portion 34d moves in the viscous
medium 54.
[0133] According to the above-described configuration, the
vibration damping performance is improved by adjusting or
optimizing the resistance of the inertia body portion 34d, and thus
the abnormal noises for suppressing the movement of the inertia
body portion 34d of the dynamic damper (corresponding to the first
dynamic damper 3c in FIG. 1) are restricted from occurring.
[0134] According to the aforementioned embodiments, the inertia
body portion 34d, the part of which is immersed in the viscous
medium 54 when the torque fluctuation reducing apparatus 3 rotates,
includes the recessed portion 34h which reduces the resistance when
the inertia body portion 34d moves in the viscous medium 54.
[0135] According to the above-described configuration, the
influence of the viscous medium (corresponding to the viscous
medium 54 in FIG. 1) is reduced by the recessed portions 34h, and
the original or the intended damping performance is ensured.
[0136] According to the aforementioned embodiments, the viscous
medium 54 corresponds to the oil or the grease of which viscosity
resistance increases as the oil or the grease cools.
[0137] According to the above-described configuration, the
viscosity resistance of the viscous medium increases in a state
where the engine is cold, and thus the resonance is restricted and
the start-up performance of the engine may be enhanced.
[0138] The principles, preferred embodiments and mode of operation
of the present invention have been described in the foregoing
specification. However, the invention which is intended to be
protected is not to be construed as limited to the particular
embodiments disclosed. Further, the embodiments described herein
are to be regarded as illustrative rather than restrictive.
Variations and changes may be made by others, and equivalents
employed, without departing from the spirit of the present
invention. Accordingly, it is expressly intended that all such
variations, changes and equivalents which fall within the spirit
and scope of the present invention as defined in the claims, be
embraced thereby.
* * * * *